Electric meter.



No'.'796,,042 PVAIT-ENTEDAUGII, 1905-. T. DUNCAN,

ELECTRIC METER.

APPLICATION FILED JULY 1 1 1 90], RBNEWED JAN. 7.1005.

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No. 796,042. v PATBNTIED AUG.1,1905.

-T.DVUNGAN. ELECTRIC METER.

APPLIOATION nun JULY 11, 1901. ngnnwnn' m. 1.1905. 7

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. T. DUN0AN.

ELECTRIC METER. APPLIUATION FILED JULY 11, 1901. RENBWBb'iAR-l. 1905- lI a nn'rs-snnnzr a.

WITNESSES IN VENTOR.

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UNITED STATES PATENT OFFICE."

THOMAS DUNCAN, OF CHICAGO, ILLINOIS.

- ELECTRIC METER.

Specification of Letters Patent.

Patented Aug. 1, 1905.

Application filed July 11, 1901. Renewed January 7,1905. Serial No.239,969.

To all whom it may concern;

Be it known that I, THOMAS DUNCAN, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Electric Meters, ofwhich the and has for its object the provision of an improved form ofmeter whose rate of operation per unit of load or energy may beautomatically varied upon predetermined change in the current suppliedto thesystem.

In the metering of energy or loads in working circuits it is desired toprovide for three different rates of operation of the counting mechanismof the meters per unit of load or energy, one rate of operation, thenormal, continuing, say, from six to six in the daytime, another rate ofoperation, the over rate that is, above the normal-continuing from sixin the evening to twelve midnight, and

another rate of operation, the under rate that is, below thenormalcontinuing from twelve midnight to six-in the morning. The reasonfor this is that the central station is usually taxed to its utmostbetween-the hours of six and twelve at night, for which, consequently,the consumer who uses power during this time should be charged at a ratein proportion to the cost of the central-station installation, which isequipped for this maximum output required at no other time. Betweentwelve and six in the morning the station is taxed the least, duringwhich time a minimum amount of apparatus is required, calling for theminimum return upon the investment. Between the hours of six to six inthe day-time the central station is not taxed to its limit, nor is ittaxed at the minimum, so that the consumer should be charged a ratewarranted by the installation necessary to supply the normal demand.Obviously these periods during which the normal, maximum,

and minimum rates of operation of the meas;

uring mechanisms per unit of energy or load are required may vary withthe season and local conditions.

In practicingmy present invention I employ automatically-operated meansin the form of an electromagnet or solenoid, which serves to 7 put uponthe system, and employ in combination with this mechanismmeansincreasing the electromotive force or pressure in thepressure-winding of the meterwhen the meter is to be operated at an overrate and to cause this secondary pressure to act as counterelectromotive force in the circuit, including the pressurewinding of themeter, when the meter is to run at an under rate, the means forcontrolling the application of the pressure to the pressure-field of themeter also serving to disconnect'the pressure-winding from thesupplemental source of pressure to permit the meter to run at the normalrate. The solenoid is preferably included in series in one of the.mains, and a rheostat is cooperatively associated with the solenoid,which rheostat by being in circuit with. the fieldwinding of thesupplemental-pressure generator automatically, through the agency of thesolenoid, controls the field, and thereby the degree of secondarypressure impressed upon the meter pressure-winding,

In the drawings, Figures 1, 2, and 3 illustrate systems of electricaldistribution with meters and controlling means of my inventionassociated therewith. Fig. 4 is a detail view of the means forcontrolling the association of the meter pressure-winding with thesecondary pressure-circuit.

Like parts are indicated by similar characters of reference throughoutthe figures.

Ineachof the figures is illustrated a generator 1 supplying current overthe transmission-mains 2 2 to the translating devices 3 3.

Consumers meters imay be located wherever a center of consumption islocatedthat is, these meters are provided for each customer. Each meter4 is in this instance illustrated in the form of a commutatedmotor-meter having its current-winding subdivided into ourrent-coils 5 5and its pressure-winding in the form of an armature 6, mounted upona'shaft upon which is located the commutator 7 that serves to connectthe pressure or armature winding in circuit, which meter may also beprovided with the usual damping-disk 8, arranged within the fields ofdamping-magnets 9 9. Meters of other construction, however. may beemployed, and I do not, therefore, wish to be limited to a commutatedmotormeter, nor do I wish to be. limited to the character of currentused in the system of distribution.

totalize the measurements of the load.

To effect a change in the rate of operation Counting-trains 10 areillustrated to v of the meter per unit of load or energy, 1 prefer toprovide automatically-operated electromagnetic devices 11, that serve tochange the field due to the pressure-winding of each meter, threeadjustments being preferably provided, one where the pressure-windingproduces a field of intermediate strength for the normal operation ofthe meter, which may occur, for example, between the hours of six andsix in the day-time, another for an overrate operation of the meterwhere the pressure is stronger as, for example, between the hours of sixand twelve at nightand the third where the pressure-field is atitsweakest to operate the meter at a minimum or under rate-as, for example,between the hours of twelve and six in the morning. Each adjustingdevice is designed by its operation to permit of the normal operation ofthe meter when the adjusting device is in one condition of operation andto permit of the excess-rate and under-rate operation of the meter whenit is in another condition of operation. I will describe an adjusting orchanging device 11 hereinafter after having first described some of theapparatus at the central station to be used in cooperation therewith.

At the central station are provided switches 12 and 18 and a governingelectromagnet or solenoid 14:, provided for the purpose of cuttingresistance 15 into and out of circuit. The helix of this solenoid ispreferably includedin series in one of the main conductors, while thecore thereof may be under proper conditions withdrawn from the helix bya coiled spring 16. The core of the solenoid may be provided with anindex registering with a scale 17 to indicate the load upon the system.The resistance 15 is in series with the field-winding 13 of a smallsupplemental generator 18. The armature 19 of the generator is connectedwith the switch 13, which according to its position may serve to supplycurrent to the armature 6 of each meter to furnish an additiveelectromotive force or a counter electromotive force.

For the purpose of including the armature 19 in circuit with themeter-armature 6 supplemental -pressure conductors 20 and 21 may beemployed, which through the agency of the controlling device 11 areeither included in circuit with or excluded from the circuit, includingthe armature 6. By means of the pole-changing switch 13 the connectionof the armarture 19 with the pressureeonductors 20 and 21 may bereversed, so that the pressure in the armature-winding 6 may beincreased when the meter is to run at an over rate, or a counterelectromotive force may be impressed upon the circuit, including thearmature 6, to decrease the field thereof to cause the meter to run atan under rate. If the meter is to run at a normal rate, thesupplemental-pressure conductors 20 and 21 are preferably cut out ofcircuit with the armature 6 by the operation of the changer 11, as willbe presently specified.

. In the preferred form of the circuit-clnmger electromagnets in theform of solenoids 22 and 23 are employed, which have a common core 24,with which one end of the centrallypivoted oscillating switch-actuatinglever 25 is engaged. The other end of the switchactuating lever isengaged with the insulating-mounting 26, upon which are mountedswitch-plates 27, 28, and 29, the support 26 being movablelongitudimtliv upon a guidingrod 30, that passes through the same.1ontact-springs 3i and 32 are connected with the suppleniental-pressureconductors 2e and 21, while contact-springs 33 and 34: constitute theterminals of the armature or pressure winding 6. \Vhen the changer 11 isin the position illustrated in Figs. 1. and 2., the springs 32 34: and31 33 are connected by means of the plates 27 and 28, whereby thesupplementalpressure conductors 20 and 21 are included in circuit withthe armature (3, so thatthearmature may be subject to an additiveelectro motive force to increase its rate 0 t operation as, for example,between the hours ol six and twelve at night- -or the armature may besubject to a counter electromotive force to decrease its rate ofoperation am, for e.\'a1nple, between the hours of twelve and six in themorning. If the meter is to run at a normal rate, the changers areplaced in the positions illustrated in Fig. 3, where the supplementalconductors 20 and 21 are cut out of circuit, the terminal-springs 33 and2-H being directly connected by the switch portion 29, in whichcondition the armature (3 is subject only to the pressure between themains.

For controlling the operation 01 the solenoids of the changers theswitch 12 is employed. \Vith the switch mechanism at the central stationin the position shown in Fig. 1 the solenoid 22 has being energized,circuit through thesame being traced from the ground 35 through thesupplementalpressure conductor 20 and the solenoid 22 to the ground 36,current being supplied from the supplemental source of pressure 18. Tocut the armature 6 out oi circuit, the switch I). is reversed, currentthen being traced from the ground 35 through the generator 18, theconductor 37, and solenoid 2;) to the grouml 36. hen thesupplemental-pressure conductors 20 and 21 are included in circuit withthe armature (5, the counter electromotive force or the additiveelectromotive force impressed upon thearmature,according to the positionof the switch 13, is automatically varied by the electromagnet orsolenoid '14:,whose core or armature cuts out resistance 1:7 on anincrease in current and permits the reinclusion of said resistance upona decrease in current, thereby rerespectively efli'ecting an increaseand decrease in the supplemental electromotive force imerator.

pressed upon the supplemental-pressu re conductors 20 and 21 and thearmature 6 in circuit therewith. Thus as the load upon the systemincreases the resistance 15 is out out to cause the armature 6 to runfaster when the supplemental electromotive force is added and to runslower when the supplemental electromotive force opposes theelectromotive force impressed upon the armature from thedistributing-mains. When normal rate is required, the switch 13 ispreferably on open circuit. In changing the meter from a normal rate toan over or under rate instrument the switch 12 is thrown to the left, asindicated in Fig. 1, and operated a number of times to insure theconnection of the armature or pressure winding with thesupplemental-pressure conductors 20 and 21, whereafter the switch 13 isthrown to the right, which may, for example, cause the meter to run atan over rate, or the switch 13 is thrown to the left if the meter is torun at an under rate, In changing the meters to instruments operating atnormal rates the switch 12 is thrown to the right and opened and closedseveral times to insure an engagement between the switch parts 29 withthe springs 33 and 34 of each changer.

To compensate for the removal and inclusion of meters, an adjustableresistance 38 may be employed in series with the pressure field-windingof the auxiliary-pressure gen- The ammeter-scale 17 serves to assist inthe adjustment of percentages.

In Figs. 2 and 3 the solenoids 22 and 23 may be operated by current fromthe mains.

While I have herein shown and particularly described the preferredembodiment of my invention, I do not wish to be limited'to the preciseembodiment thereof herein set forth, as it is obvious that changes mayreadily be made without departing from the spirit thereof; but- 7 Havingthus described my invention, I claim as new and desire to secure byLetters Patent 1. The combination with a current-generator, of a meter,a supplemental-pressure generator, means for changing the pressure ofthis generator, a solenoid for governing the.

means, the said solenoid being subject to the current in the system,thereby having its strength Vary with the current whereby thesupplemental pressure is correspondingly varied, and conductors forincluding a winding of the meter in circuit with thesupplementalpressure generator, substantially as described.

2. The combination with a current-generator, of a meter, asupplemental-pressure generator, means for changing the pressure of thisgenerator, a solenoid for governing the means, the said solenoid beingsubject to the current in the system, thereby having its strength varywith the current, whereby the supplemental pressure is correspondinglyvaried, conductors for including a winding of the meter in circuit withthe supplementalpressure generator, and a' pole changing switch forchanging the direction of the sup plemental pressure,substantially asdescribed.

3. The combination with a current-generator, of a meter, asupplemental-pressure generator, means for changing the pressure of thisgenerator, a solenoid for governing the means, the said solenoid beingsubject to the current in the system, thereby having its strength varywith the current, whereby the supplemental pressure is correspondinglyvarled, conductors for includlng the pressuredescribed.

4. The combination with a current-generator, of a meter, asupplemental-pressure generator, means for changing the pressure of thisgenerator, a solenoid for governing the means, thesaid solenoid beingsubject to the current in the system, thereby having its strength varywith the current whereby the supplemental pressure is correspondinglyvarled, conductors for lncludlng the pressurewinding of the meter incircuit with the sup plemental-pressure generator, a pole-changingswitch for changing, the direction of the supplementalpressure,switching mechanism for including the pressure-winding of themeter incircuit with the,supplemental-pressure conductors and eXcludingthepressure-winding of the meter from circuit with these conductors,electromagnetic mechanism for controlling the operationof theswitchingmechanism, and switching mechanism at the central station foroperating the electromagnetic mechanism, substantially as described.

5. The combination with a current-generator, of a meter, asupplemental-pressure generator, a resistance 15 in circuit with awinding of the supplemental-pressure generator, a switching device forcutting sections of the resistance into and out of circuit with the saidsupplemental-generator winding, a solenoid for operating the saidswitching device, said solenoid being subject to the current in thesystem, thereby having its strength vary with the current, whereby thesupplemental pressure is correspondingly varied through the agency ofthe said resistance and the switching device associated therewith, andconductors for including the pressure-winding of the meter in circuitwith the supplemental-pressure generator, substantially'as described. 6.The combination with a current-generator, of a meter,asupplemental-pressure generator, a resistance 15 in series with thefieldwinding of the supplemental-pressure generator, a switching devicefor cutting sections of the resistance into and out of circuit with thesaid supplemental-generator winding, a solenoid for operating the saidswitching device, said solenoid being subject to the currentin thesystem, thereby having its strength vary with the current, whereby thesupplemental pressure is correspondingly varied through the agency ofthe said resistance and the switching device associated therewith, andconductors for including the pressure-winding of the meter in circuitwith the supplemental-pressure generator, substantially as described.

7. The combination with a current-generator, ofasupplemental source ofpressure, meters each having current and pressure windings located at adistrict of consumption, conductors for impressing the pressure from thesupplemental -pressure generator upon the pressure-windings of themeters, and an adjusting device 38 to adjust the supplemental pressureto the number of meters in the system, substantially as described.

8. In a system of electrical distribution, the combination with anelectric meter, of a supplemental-pressure generator, means for varyingthe pressure of this generator in proportion to the variation of currentin the system, and conductors for including a winding of the meter incircuit with the supplemental-pressure generator, substantially asdescribed.

9. 1n asystem of electrical distribution, the combination with anelectric meter, of a supplemental-pressure generator, automaticelectromagnetic means for varying the pressure of this generator inproportion to the variation of current in the system, and conductors forincluding a winding of the meter in circuit with thesupplemental-pressure generator, substantially as described.

10. The combination with a current-generator, of a meter, asupplemental-pressure generator, electromagnetic means for changing thepressure of this generator, and conductors for including a winding ofthe meter in circuit with the supplemental-pressure generator,substantially as described.

11. The combination with a current-generator,of a meter, asupplemental-pressure generator, means for changing the pressure of thisgenerator, an electromagneticdevice for governing the means, the saidelectromagnetic device being subject to the current in the system,thereby having its strength vary with the current whereby thesupplemental pressure is correspondingly varied, and conductors forincluding a winding of the meter in a circuit with thesupplemental-pressure generator, substantially as described.

12. The combination with a current-generator, of a meter,asupplemental-pressure generator, means for changing the pressure ofthis generator, an electromagnetic device for governing the means, thesaid electromagnetic device being subject to the current in the system,thereby having its strength vary with the current, whereby thesupplemental pressure is correspondingly varied, conductors forincluding a winding of the meter in circuit with thesupplemental-prcssure generator, and a pole-changing switch for changingthe direction of the supplemental pressure, substantially as described.

13. The combination with a current-generator, of a meter, asupplcn'iental-pressure generator, means for changing the pressure ofthis generator, an electromagnetic device for governing the means, thesaid electromagnetic device being subject to the current in the system,thereby havingits strength vary with the current, whereby thesupplemental pressure is correspondingly varied, conductors forincluding the pressure-winding of the meter in circuit with thesupplemental-pressure generator, switching mechanism for including thepressure-winding of the meter in circuit with the supplemental-pressureconductors and excluding the pressure-winding of the meter from circuitwith these conductors, electromagnetic mechanism for controlling theoperation of the switching mechanism, and switching mechanism at thecentral station for operating the electromagnetic mechanism,substantially as described.

14. The combination with a current-generator, of a meter, atsupplemental-pressure generator, means for changing the pressure of thisgenerator, an electromagnetic device for governing the means, the saidelectromagnetic device being subject to the current in the system,thereby having its strength vary with the current, whereby thesupplemental pressure is correspondingly varied, conductors forincluding the pressure-winding of the meter in circuit with asupplemental-pressure generator, a pole-changing switch for changing thedirection of the supplemental pressure, switching mechanism forincluding the pressure-winding of the meter in circuit with thesupplemental-pressure conductors and excluding the pressure-winding ofthe meter from circuit with these conductors, electromagnetic mechanismfor controlling the operation of the switching mechanism, and switchingmechanism at the central station for operating the electromagneticmechanism, substantially as described.

15. The combination with a current-generator, of ameter, asupplemental-pressure generator, a resistance 15 in circuit with awinding of the supplemental-pressure generator, a switching device forcutting sections of the resistance into and out of circuit with the saidsupplemental-generator winding, an electromagnetic device for operatingthe said switching device, said electromagnetic device being 7 subjectto the current in the system, thereby having its strength vary with thecurrent,

1 whereby the supplemental pressure is correspondingly varied throughthe agency of the said resistance and the switching device as sociatedtherewith, and conductors for including the pressure-winding of themeter in circuit with the supplemental-pressure generator, substantiallyas described.

16. The combination with a current-generator, of a meter, a supplemental-pressure generator, a resistance 15 in series with thefieldwinding of the supplemental-pressure generator, a switching devicefor cutting sections of the resistance into and out of circuit with thesaid supplemental-generator wind ing, an electromagnetic device foroperating the said switching device, said electromagnetic device beingsubject to the current in the system, thereby having its strength varywith namethis 23d day of May,

the current, whereby the supplemental pressure is correspondingly variedthrough the agency of the said resistance and the switching deviceassociated therewith, and conductors for including the pressure-windingof the meter in circuit with the supplemental-pressure generator,substantially as described.

17. The combination with a generator, of a meter, a supplementalpressure generator, and means for changing the pressure of thisgenerator, a winding of the meter being in circuit with thesupplemental-pressure generator, substantially as described,

In witness whereof I hereunto subscribe my THOMAS DUNCAN.

Witnesses: GEORGE L. CRAee,

HERBERT F. OBERGFELL.

